1. Field of the Invention
The present invention relates to a straddle-type four wheeled all terrain vehicle, and more particularly to an intake structure of a cooling air for a straddle-type four wheeled all terrain vehicle in which a belt converter is mounted to an engine.
2. Description of the Related Art
In the straddle-type four wheeled all terrain vehicle, a belt converter is sometimes mounted to an engine. The belt converter is mounted between a crank shaft of the engine and a transmission to facilitate a speed change operation of a vehicle.
The belt converter is accommodated in a case. Since the belt converter generates heat by an operation thereof, an air is introduced from outside into the case, thereby cooling the belt converter to prevent an increase in temperature in the case.
An example of the intake structure of the cooling air into the belt converter is that a box-shaped space opened at a front and closed at a periphery thereof is provided in a lower portion of a tip end portion of a front fender and an air passage reaching the belt converter is opened in this space (see Japanese Patent No. 2963052).
However, in this structure, when the vehicle is traveling, foreign substances such as trash, mud, water as well as fresh air from front, sometimes enter the intake port. For this reason, there is a need for an improved intake structure of the cooling air into the belt converter.
The present invention addresses the above-described problem, and an object of the present is to provide a straddle-type four wheeled all terrain vehicle having an intake structure of a cooling air into a belt converter that is capable of preventing the entry of foreign substances such as water and mud with a simple constitution.
According to the present invention, there is provided a straddle-type four wheeled all terrain vehicle comprising: a vehicle body; a straddle-type seat provided on an upper portion of the vehicle body; a bar-type handle having a steering shaft and provided forward of the seat; a vehicle body cover covering a portion of the vehicle body including the steering shaft from above, the steering shaft penetrating through the vehicle body cover; and a belt converter, wherein an opening of the vehicle body cover through which the steering shaft passes is an intake port of a cooling air into the belt converter.
With this constitution, since the intake port through which the cooling air is taken into the belt converter from outside is provided at the middle in the longitudinal direction of the vehicle body and at a high position of the vehicle body, the water, mud or the like hardly enters the intake port. Besides, since the opening of the vehicle body cover through which the steering shaft passes is utilized, the intake port can be structured very simply. Also, the intake port is formed around the steering shaft of the handle and just before the rider, and therefore, if the intake port is clogged with the foreign substances or the like, they can be immediately found and removed.
Preferably, in the straddle-type four wheeled all terrain vehicle, a relay chamber may be formed inside of the vehicle body cover such that the relay chamber communicates with the opening, and a cooling air intake port of the belt converter may be opened in the relay chamber.
Thereby, the cooling air intake passage from the opening of the vehicle body cover to the belt converter can be easily constituted.
Preferably, in the straddle-type four wheeled all terrain vehicle, a portion of the vehicle body cover around the opening may be raised to be formed into a swelled portion, and the relay chamber may be structured to have a chamber wall including one part constituted by a portion of the swelled portion including the opening and the other part through which the steering shaft and a cooling air intake duct having the cooling air inlet port of the belt converter that is opened in the relay chamber penetrate.
Thereby, the intake port through which the cooling air is taken into the belt converter can be formed at a high position because of the swelled portion. In addition, since the swelled portion is utilized as part of the chamber wall, the relay chamber can be easily constituted.
Preferably, in the straddle-type four wheeled all terrain vehicle, a portion of the other part of the chamber wall through which at least the steering shaft and the cooling air intake duct of the belt converter penetrate may be comprised of a flexible plate member.
Since the flexible plate member is flexible, steering shaft, the cooling air intake duct, or the like can be easily made to penetrate through the corresponding through holes even if some positional difference occurs between these members and the through holes.
Preferably, in the straddle-type four wheeled all terrain vehicle, the swelled portion may be configured such that front and side portions around the opening is raised and the swelled portion extends rearwardly, the relay chamber may be structured such that a portion of the swelled portion defines one part of the chamber wall of the relay chamber, a front wall member, a pair of side wall members, a flexible plate member, and a seal structure define the other part of the chamber wall, the front wall member and the pair of side wall members are downwardly protruded at a front end portion and side end portions of the swelled portion that is located forward and side of the opening in an inner face of the vehicle body cover such that the front wall member and the side wall members form an enclosure, the flexible plate member substantially defines a bottom and a rear of a space covered by the portion of the swelled portion that is located forward and side of the opening, the seal structure is formed between a front end of the flexible member and a lower end of the front wall member, and the steering shaft and the cooling air intake duct of the belt converter may penetrate through the flexible plate member.
With this constitution, a wide relay chamber can be formed. Besides, since the bottom wall and the rear wall of the relay chamber can be formed by one flexible member, its structure can be simplified. Further, since the seal structure is provided at the front lower portion of the relay chamber that tends to be splashed with mud or water, the entry of the mud, water, or the like into the relay chamber can be prevented.
Preferably, in the straddle-type four wheeled all terrain vehicle, the seal structure may be formed such that a support member being a frame member of the vehicle body extends along a lower end of the front wall member as having a clearance between the front wall member and the support member, a cushion member may be provided on the support member to fill the clearance, and a front end of the flexible plate member may be connected to the support member.
Thereby, the seal structure can be easily formed.